• Title/Summary/Keyword: constant-release

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Effect of Panax Ginseng Saponin on Metabolism and Ion Transport in Human Erythrocytes (인삼이 적혈구세포의 해당과정 및 막 투과도에 미치는 영향)

  • Kang, Bok-Soon;Han, Kyung-Hee
    • The Korean Journal of Physiology
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    • v.17 no.2
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    • pp.125-133
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    • 1983
  • Red cell glycolytic intermediates, metabolites and metabolic ratios were studied. Glycolytic intermediates were measured in neutralized perchloric acid extracts of red cell suspensions after 3 hr incubation at $37^{\circ}C$ in the presence and absence of saponin. Adenosine triphosphate(ATP), adenosine diphosphate(ADP), pyruvate and lactate were measured by enzymatic procedures involving stoichiometric oxidation or reduction of a pyridine nucleotide. Glucose was determined using glucose oxidase after zinc hydroxide extraction. The redox state was calculated from the lactate dehydrogenase equilibrium. Adenosine triphosphatase activity(ATPase) was measured by determining the amount of phosphate released from ATP by washed erythrocyte membranes(ghost) during 20 min. incubation. Both total hydrolysis and the amount of hydrolysis that occured in the presence of ouabain were measured. The second measurement yields Mg-ATPase and represents nonspecific ATPase activity of the membranes. The difference between total and Mg-ATPase activity can be attributed to Na-K-ATPase. For the measurement of sodium fluxes, human erythrocytes were preincubated in $^{22}Na$ for 3 hr at $37^{\circ}C$, washed and suspended in a tracer-free medium. The amount of $^{22}Na$ transported out of cells at any time was determined by analysis of supernatant samples taken at various time after addition of the labeled cells to isotope-free medium. The cells and medium were separated and the radioactivity appearing in the medium was measured. From the total radioactivity in the suspension and the radioactivity appearing in the medium at known time, the rate constant for sodium release was computed. The results are summarized as follows: 1) ATP and ATP/ADP were found to increase at every concentration of saponin tested whereas ADP declined at every cone. of saponin. The increase in pyruvate and lactate were observed at every cone, of saponin and thus $NAD^+/NADH$ computed from pyruvate/lactate also increased. Glucose utilization was stimulated by saponin. 2) $Na^+-K^+-ATPase$ activities showed a biphasic response to saponin, first increasing in lower concentration and then decreasing in higher concentration of saponin. 3) The efflux of sodium was significantly increased by saponin in the range of 5 to 10 mg%. The stimulatory effect of saponin on the rate constants for active(ouabain-sensitive) sodium efflux was inhibited by addition of ouabain.

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Effects of $H^{+}$ on the Contraction Induced by Various Agonists in the Renal Artery of a Rabbit (수소이온농도 변화의 수축물질에 따른 가토신동맥 수축에 미치는 영향과 기전)

  • Chang, Seok-Jong;Kim, Se-Hoon;Jeon, Byeong-Hwa;Park, Hae-Kun
    • The Korean Journal of Physiology
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    • v.24 no.1
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    • pp.161-170
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    • 1990
  • The effects of $H^{+}$ on the arterial contraction and their mechanisms were investigated in the renal artery of a rabbit. The helical strips of isolated renal artery were immersed in the HEPES-buffered or $CO_{2}/HCO_{3}^{-}$-buffered Tyrode's solution. The contractions induced by agonists (norepinephrine, histamine, serotonin and angiotensin II) or high $K^{+}$ were observed with change of extracellular or intracellular $H^{+}$ concentration. The contractions induced by norepinephrine, histamine, serotonin, angiotensin II or high $K^{+}$ in HEPES-buffered Tyrode's solution were inhibited by increase in extracellular $H^{+}$ concentration and potentiated by decrease in extracellular $H^{+}$ concentration. The degrees of these effects were most evident in the contraction induced by serotonin and angiotensin II, moderate in those by histamine and high $K^{+}$, and least in those by norepinephrine. Maximal contraction by norepinephrine, histamine and high $K^{+}$ were not influenced by change in extracellular $H^{+}$ concentration, but influenced in those contration by serotonin and angiotensin II. The attenuated contractions by an acidic pH were not returned to the level of contraction at normal pH (7.4) by elevation of extracellular $Ca{2+}$ concentration. The agonists (norepinephrine, histamine and serotonin)-induced contractions in $Ca{2+}$-free Tyrode's solution were also attenuated by increase in extracellular $H^{+}$ concentration and potentiated by decrease in extracellular $H^{+}$ concentration. Elevation of $Pco_{2}$ in the $CO_{2}/HCO_{3}^{-}$-buffered Tyrode's solution, which increase the intracellular $H^{+}$ concentration, at constant extracellular pH (7.4), increased the contraction by 30 mM $K^{+}$. From the above results, it is suggested that the decrease in contractions by increase in extracellular $H^{+}$ concentration may be resulted from that $H^{+}$ make the receptors less sensitive to agonists and cell membrane hyperpolarize and then inhibit the $Ca{2+}$ influx as well as $Ca{2+}$ release from intracellular $Ca{2+}$ storage site.

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The Effect of decalcified Root Surface as PDGF Carrier (PDGF 함유매개체로서 탈회된 치근면의 효과)

  • Woo, Hyo-Sang;Lee, Jae-Mok;Suh, Jo-Young
    • Journal of Periodontal and Implant Science
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    • v.26 no.4
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    • pp.889-905
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    • 1996
  • It is known that growth factors function as potent biologic mediators regulating numerous activities of wound healing via cell proliferation, migration and extracellular matrix formation and they also promote periodontal regeneration. But, method of growth factor application is controversial yet. So purpose of this study is to evaluate the effect of demineralized root surface as one of method of growth factor application. The ginigival fibroblasts were primary cultured and fifth or sixth subpassages were used in these experiments. In first experiment, root surface blocks demineralized with 100mg/ml tetracycline for 5 minutes and pH 1 citric acid for 3 minutes(experimental groups) and nonteminerilized root surface blocks (control groups) were placed in 100ng/ml PDGF-BB for 5 minutes. Then the cells were seeded on each root surface blocks and cultured for 6, 24, 48, 72 hours. In second experiment, root surface blocks deminerilized with tetracycline and citric acid and nondemineralized root surface blocks were placed in 200ng/ml PDGF-BB for 5 minutes and another non-demineralized root surfcae blocks were placed in DMEM without PDGF-BB. At 1, 2, 4, 6, 8 days, the cells were seeded in 24-well plate and using of each eluent, cultured for 72 hours. The results of the four determinants were presented as mean and S.D.. The results were as follows : The attachment and proliferation of human gingival fibroblast on root surface were more increased when PDGF-BB was applicated on root surfrace demineralized with tetracycline or citric acid than non-demineralized root surface. And, in comparision tetracycline with citric acid, there were more attachment and proliferation of human gingival fibroblast on root surface demineralized with tetracycline than citric acid, and proliferation of human gingival fibroblast on demineralized root surface was increased time dependently 1 day to 3 days. In second experiment using eluent, proliferation of human gingival fibroblast was more increased to 6 days when human gingival fibroblast was cultured in eluent that PDGF-BB was applicated on demineralized root surface than two control groups, and degree of proliferation was decreased time dependently 1 day to 6 days. Proliferation of human gingival fibroblast cultured in eluent without PDGF-BB was constant 1 day to 6 days. After 6 days, degree of proliferation of human gingival fibroblast was similar in four groups. This means that release duration of PDGF-BB from demineralized root surface is 6 days. And in comparision tetracycline with citric acid, there was more proliferation of human gingival fibroblast in tetracycline-treated group than citric acid. In conclusion, demineralized root surface as primary site for PDGF-BB application, especially demineralized with tetracycline has important roles in attachment and proliferation of human gingival fibroblast, and may be useful clinical applications in periodontal regenerative procedures.

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A Nuclide Transfer Model for Barriers of the Seabed Repository Using Response Function (응답함수를 이용한 해저처분장의 방벽에 대한 핵종전달 모델)

  • Lee, Youn-Myoung;Kang, Chul-Hyung;Hahn, Pil-Soo
    • Nuclear Engineering and Technology
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    • v.28 no.2
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    • pp.175-184
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    • 1996
  • A nuclide transfer by utilizing mass transfer coefficient and barrier response function defined for each barrier is proposed, by which the final nuclide transfer rate into the sea water can be evaluated. When simple and immediate quantification of the nuclide release is necessary in the conservative aspect, using this kind of approach may be advantageous since each layered barrier can be treated separately from other media in series in the repository system, making it possible to apply separate solutions in succession to other various media. Although one disadvantage is that while flux continuity can be maintained at the interface by using the exit nuclide flux from the first medium as the source flux for the next one, there may be no guarantee for concentration continuity, this problem could be eliminated assuming that there is no boundary resistance to mass transfer across the interface. Mass transfer coefficient can be determined by the assumption that the nuclide concentration gradient at the interface between adjacent barriers remains constant and barrier response function is obtained from an analytical expression for nuclide flow rate out of each barrier in response to a unit impulse into the barrier multiplied by mass transfer coefficient. Total time-dependent nuclide transfer rate from the barrier can then be obtained by convoluting the response function for the barrier with a previously calculated set of time-varying input of nuclide flow rate for the previous barrier.

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An Evaluation of Soil-Water Characteristic Curve Model for Compacted Bentonite Considering Temperature Variation (온도 변화를 고려한 압축 벤토나이트 완충재의 함수특성곡선 모델 평가)

  • Yoon, Seok;Jeon, Jun-Seo;Go, Gyu-Hyun;Kim, Geon-Young
    • Journal of the Korean Geotechnical Society
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    • v.36 no.10
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    • pp.33-39
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    • 2020
  • A geological repository has been considered as an option for the disposal of high-level radioactive waste (HLW). The HLW is disposed in a host rock at a depth of 500~1,000 meters below the ground surface based on the concept of engineered barrier system (EBS). The EBS is composed of a disposal canister, buffer material, backfill material, and gap-filling material. The compacted bentonite buffer is very important since it can restrain the release of radionuclide and protect the canister from the inflow of ground water. The saturation of the buffer decreases because high temperature in a disposal canister is released into the surrounding buffer material, but saturation of the buffer increases because of the inflow of ground water. The unsaturated properties of the buffer are critical input parameters for the entire safety assessment of the engineered barrier system. In Korea, Gyeongju bentonite can be considered as a candidate buffer material, but there are few test results of the unsaturated properties considering temperature variation. Therefore, this paper conducted experiment of soil-water characteristic curve for the Gyeongju compacted bentonite considering temperature variation under a constant water content condition. The relative error showed approximately 2% between test results and modified van-Genuchten model values.

A Study on Optimal Operation for Flare systems (플레어 시스템의 최적 운영방안에 대한 연구)

  • Song, Bang-Un;Bok, Hyeong-Jun;Woo, In-Sung
    • Journal of the Korean Institute of Gas
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    • v.23 no.6
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    • pp.1-7
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    • 2019
  • Most oil refineries and chemical plants have flare systems designed to mitigate pressure rises in process facilities in case of emergencies that require the release of large amounts of gas due to sudden process shutdowns such as power outages. However, the rise of the flame of the flare system causes civil complaints from residents around the factory due to visible pollution, and economic loss occurs in the company, which requires constant management. In this study, two items were diagnosed and analyzed in order to derive the optimal operation method of flare system. First, to detect the cause of the rise in flame height, the acoustic leak detector was used to check gas leaks in safety valves and pressure control valves. Second, to identify the cause of flame instability, the pulsation phenomenon was diagnosed through the CFD simulation and modeling experiments of the sealing drum. By confirming the leak at 4.3% of the safety valve and 10% of the pressure control valve, the cause of abnormal sparking was derived. The information presented in this study can be easily applied to any company that has a flare system, and is expected to prevent complaints and product loss.

Identification of Muscle Proteins Related to Objective Meat Quality in Korean Native Black Pig

  • Hwang, I.H.;Park, B.Y.;Cho, S.H.;Kim, J.H.;Choi, Y.S.;Lee, J.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.11
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    • pp.1599-1607
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    • 2004
  • This study examined the effects of pre-slaughter fasting, chasing stress and chiller ageing on objective meat quality, and their relations to the proteome profile of longissimus muscle using 20 male Korean native black pigs. Treatments were composed of two levels of pre-slaughter feed withdrawal, two levels of pre-slaughter stress and four chiller ageing times. A 15 min chasing stress immediately prior to slaughter significantly (p<0.05) decreased detectable levels of $\mu$-calpain activity during rigor development and chiller ageing, but did not have any direct effect on objective meat quality. On the other hand, pigs fed until the morning of slaughter resulted in significantly (p<0.05) higher hunter L* value and cooking loss than those which received an 18 h feed withdrawal prior to slaughter. Cooking loss and hunter L* value were constant during 7 d of chiller ageing, followed by significant increases at 14 d. The fed animals showed a significantly (p<0.05) higher hunter a* value at both 3 and 7 d, while the other group maintained a stable redness for 7 d. WB-shear force was not affected by the pre-slaughter treatments, but had significant (p<0.05) linear reduction from 1 to 7 d. A gelbased proteome analysis was performed on selected animals for low and high hunter L* values at 1 d. Ten and five spots had greater than two-fold spot densities for the low and high hunter L* groups, respectively. The ten spots included chain A, deoxyribounclease I complex with actin, heat shock protein 27 kDa, a protein similar to cardiac $Ca^{2+}$ release channel, and myosin heavy chain, while the five spots included chain A aldehyde dehydrogenase, glycerol-3 phosphate dehydrogenase, and hemoglobin alpha chain. In general, feeding until the morning of slaughter resulted in more desirable meat color, but appeared to reduce palatability due to increased cooking loss. Proteome analysis demonstrated that various proteins were concomitantly involved in the determination of final meat color. The most noticeable observation in the current study was that various isoforms for a particular protein differed in degradation and/or expression rate depending on meat quality.

Improvement on the KFOOD Code for More Realistic Assessment of the Annual Food Chain Radiation Dose Due to Operating Nuclear Facilities (가동중 원자력 시설에 의한 년간 섭식경로 피폭선량 평가의 현실성 제고를 위한 KFOOD 코드의 개선)

  • Park, Yong-Ho;Lee, Chang-Woo;Kim, Jin-Kyu;Lee, Myung-Ho;Lee, Jeong-Ho
    • Nuclear Engineering and Technology
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    • v.25 no.3
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    • pp.437-446
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    • 1993
  • More realistic calculation models for evaluating man's annual intakes of radionuclides released from operating nuclear facilities were established. For the application of these models, the harvest years of food and feed crops consumed in the year of dose assessment and every year's average concentrations of a radionuclide in air and in water for the whole period of real operation had to be taken into account. KFOOD, an existing equilibrium food chain computer code for the Korean dose assessment, was modified according to the models. Sample runs of the modified code on the assumption of a constant release during 10 years' operation were made with three kinds of the input data files enabling the dose assessment in the improved method, the KFOOD method and another existing method, respectively, and the results were compared. Annual committed effective doses to Korean adult by intakes of Mn-54, Co-60, Sr-90, I-131 and Cs-137 calculated in the improved method were about 11, 2, 5, 60 and 3%, respectively, lower than the corresponding KFOOD dose. To the intakes of the radionuclides except Sr-90 evaluated in the improved method, foliar uptake contributed much more than root uptake did but, in the case of Sr-90, the result was opposite.

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Plant-derived Anti-HIV Natural Products: A Review of Recent Research (천연물의 항 HIV 효능에 대한 최신 연구동향)

  • Karadeniz, Fatih;Oh, Jung Hwan
    • Journal of Life Science
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    • v.32 no.9
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    • pp.734-741
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    • 2022
  • Currently, around 40 million people worldwide are living with human immunodeficiency virus (HIV) infection making HIV a critical global health risk. Present therapies for HIV infection consist of drug cocktails that target different steps of the HIV life cycle to prevent infection, replication, and release of the virus. Due to its mutating nature, drug resistance coupled with side-effects of long-term drug use, novel strategies, and pharmaceuticals to treat and manage HIV infection are constant needs and continuously being studied. Plants allocate a major repertoire of chemical diversity and are therefore regarded as an important source of new bioactive agents that can be utilized against HIV. Since the early 1990s, upon recommendations of the World Health Organization, numerous studies reported phytochemicals from different structural classes such as flavonoids, coumarins, tannins and terpenes with strong inhibitory effects against HIV infection. The present review gathered and presented recent research (2021-present) on plant extracts and phytochemicals that exhibit anti-HIV properties with the aim of providing insights into future studies where ethnomedical and underutilized plant sources may yield important natural products against HIV. Considering the relation and importance of HIV treatment with current viral infection risks such as SARS-CoV-2, screening plants for anti-HIV agents is an important step towards the discovery of novel antivirals.

Pharmacoacupuncture for the Treatment of Frozen Shoulder: protocol for a systematic review and meta-analysis

  • Ji-Ho Lee;Hyeon-Sun Park;Sang-Hyeon Park;Dong-Ho Keum;Seo-Hyun Park
    • Journal of Pharmacopuncture
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    • v.27 no.1
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    • pp.14-20
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    • 2024
  • Objectives: Frozen shoulder (FS) is one of the most challenging shoulder disorders for patients and clinicians. Its symptoms mainly include any combination of stiffness, nocturnal pain, and limitation of active and passive glenohumeral joint movement. Conventional treatment options for FS are physical therapy, nonsteroidal anti-inflammatory drugs, injection therapy, and arthroscopic capsular release, but adverse and limited effects continue to present problems. As a result, pharmacoacupuncture (PA) is getting attention as an alternative therapy for patients with FS. PA is a new form of acupuncture treatment in traditional Korean medicine (TKM) that is mainly used for musculoskeletal diseases. It has similarity and specificity compared to corticosteroid injection and hydrodilatation, making it a potential alternative injection therapy for FS. However, no systematic reviews investigating the utilization of PA for FS have been published. Therefore, this review aims to standardize the clinical use of PA for FS and validate its therapeutic effect. Methods: The protocol was registered in Prospero (CRD42023445708) on 18 July 2023. Until Aug. 31, 2023, seven electronic databases will be searched for randomized controlled trials of PA for FS. Authors will be contacted, and manual searches will also be performed. Two reviewers will independently screen and collect data from retrieved articles according to predefined criteria. The primary outcome will be pain intensity, and secondary outcomes will be effective rate, Constant-Murley Score, Shoulder Pain and Disability Index, range of motion, quality of life, and adverse events. Bias and quality of the included trials will be assessed using the Cochrane handbook's risk-of-bias tool for randomized trials. Meta analyses will be conducted using Review Manager V.5.3 software. GRADE will be used to evaluate the level of evidence for each outcome. Results: This systematic review and meta-analysis will be conducted following PRISMA statement. The results will be published in a peer-reviewed journal. Conclusion: This review will provide scientific evidence to support health insurance policy as well as the standardization of PA in clinical practice.